Case 1: What is the most likely diagnosis?
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Case 1: What is the most likely diagnosis?
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Fluid Filled Laryngocele
Case 1a: What is the most likely diagnosis?
A laryngocele is caused by dilatation of the laryngeal ventricle, which may be congenital or acquired. Acquired causes are usually due to increased supraglottic pressure (brasswind instrument players, chronic coughers). The laryngocele displays well-defined margins on CT (red arrows) with homogeneous fluid or air CT attenuation. The fluid component on T1- and T2-weighted MR images may be variable depending on the protein contents. Coronal reconstructed images are useful in localizing the laryngocele to the region of the laryngeal ventricle. Laryngoceles may also arise from obstruction of the ventricle by coexistent malignant tumors, inflammatory lesions, or other mass lesions. Patients commonly present with voice hoarseness, dyspnea, and reflex cough. They may become infected causing a laryngopyocele.
DDx: Laryngocele 1. 2. 3. 4. 5.
Laryngeal Neoplasm Submucosal Cyst Laryngeal Abscess Laryngopyocele Pharyngocele
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DDx
DDx: Pharyngocele
Case 2: What 1.is Laryngocele the most likely diagnosis? 2. Normal Pyriform Sinus
Pharyngocele A pharyngocele is a lateral bulging of the pharyngeal wall (red arrows). They are usually caused by frequent prolonged high intrapharyngeal pressure with gradual loss of muscular resilience. Pharyngoceles arise from the lateral wall of the pyriform sinus or tonsillar fossa. Congenital types result from branchial cleft remnants and are usually unilateral. Acquired pharyngocele typically arise in one of two weak areas: (1) junction of the superior and middle pharyngeal constrictor muscles at the inferior pole of the tonsil and lateral vallecula, (2) between the middle and inferior pharyngeal constrictor muscles and the thyrohyoid membrane at the base of the pyriform fossa. Symptoms may include neck or throat pain, otalgia, dysphagia, regurgitation, dysphonia, and cough.
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DDx
Case 3: What is the most likely diagnosis?
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DDx: Submucosal Cyst
Case 3a: What is the most likely diagnosis? 1. Nasopharyngeal Angiofibroma 2. Nasopharyngeal Tumor 3. Thornwaldt's Cyst
Submucosal Cyst in Fossa of Rosenmuller Most submucosal cysts are usually less than 1 cm in size and are asymptomatic; often being found incidentally. They usually show very bright signal on T2-weighted images (red arrows) and can be either bright or dark on T1-weighted images depending on the protein content. When the cysts are hyperintense on T1-weighted images, they are usually slightly hypointense on T2-weighted scans. Mild peripheral enhancement is usually seen.
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DDx
DDx: Vallecular Submucosal Cyst
Epidermoid Case 4: 1.What isCystthe most likely diagnosis? 2. 3. 4.
Thyroglossal Duct Cyst Enteric Duplication Cyst Papillomatosis
Vallecular Submucosal Cyst Vallecular cyst and pre-epiglottic cysts are rare but recognized causes of respiratory distress shortly after birth and in early infancy. They are benign lesions but may occasionally cause serious airway obstruction. In adults, they develop due to obstruction of a mucous secreting gland at the base of the tongue. The lesion gradually increases in size with accumulation of fluid or mucoid secretions. These cysts are submucosal in location and, therefore, may be missed at endoscopy when small. They are best seen on CT or MR imaging studies. On CT, vallecular cysts are seen as nonenhancing, fluid density lesions centered on the mucosa of the vallecula (red arrows). When infected, vallecular cysts may demonstrate increased density and enhance heterogeneously, making them indistinguishable from an abscess.
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DDx
DDx: Thornwaldt (Tornwaldt) Cyst
Case 5: 1.What is the Submucosal Cyst most likely diagnosis? 2. 3. 4. 5.
Rathke Cleft Cyst Adenoidal Retention Cyst Encephalocele Meningocele
Thornwaldt (Tornwaldt) Cyst The pharyngeal bursa (Thornwaldt bursa) represents a persistent communication between the roof of the nasopharynx and the notochord. Thornwaldt cysts are often detected as incidental findings on cross-sectional imaging and autopsy studies. MRI is the exam of choice to delineate and characterize this entity. The presence of protein within the cyst leads to high signal intensity on both T1- and T2-weighted images (red arrows). High T1-W MR signal intensity will usually exclude a neoplasm. Thornwaldt cyst are midline, usually unilocular, lesions situated between the longus capitus muscles. They are homogeneous and fluid-like in texture with no evidence of an adjacent mass lesion. Fat-saturated T1W post-contrast enhanced images usually show minimal peripheral enhancement.
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DDx
Case 6: What is the most likely diagnosis?
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Case 6: What is the most likely diagnosis?
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1st Branchial Cleft Cyst (Type I)
Case 6: What is the most likely diagnosis?
Branchial cleft cysts are benign lesions that arise from embryologic precursor that develops into the tissue of the neck. The branchial clefts that are important in the neck are the 1st-4th ones. Lesions from branchial cleft remnants may arise anywhere along the course of their internal opening, tract of descent, or external openings. When a branchial cleft does not completely involute, a branchial cleft cyst may form along the tract of descent. The 1st branchial cleft forms the EAC. Type I cysts are located near the external auditory canal, parotid gland, or angle of the mandible. MRI is superior to CT for imaging 1st branchial cleft cysts as they be imbedded within the parotid gland and better characterized by MRI. Branchial cleft cysts have a variable appearance on T1- and T2-weighted scans depending on their protein content (red arrows). Uninfected branchial cleft cyst should not enhance on MRI.
DDx: 1st Branchial Cleft Cyst 1. 2. 3. 4. 5.
Lymphangioma Metastatic Squamous Cell Carcinoma Cystic Hygroma Dermoid Cyst Lipomas
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DDx
Case 6a: 2nd Case of 1st Branchial Cleft Cyst
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1st
Branchial Cleft Cyst
1. Lymphangioma Case 6a: 2nd Case of 1st Branchial Cleft Cyst 2. 3. 4. 5.
Metastatic Squamous Cell CA Cystic Hygroma Dermoid Cyst Lipoma
1st Branchial Cleft Cyst (Type I) The 1st branchial cleft forms a portion of the EAC. Therefore a 1 st branchial cyst may extend along a tract to drain into the EAC (red arrows).
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DDx
Case 7: What is the most likely diagnosis?
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Case 7: What is the most likely diagnosis?
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2nd Branchial Cleft Cyst
Case 7: What is the most likely diagnosis?
95% of branchial anomalies arise from the 2 nd branchial cleft. They most frequently present an asymptomatic swelling along the anterior border of the upper third of the sternocleidomastoid and just under the angle of the mandible. Branchial cleft tracts are linear rounded tracts that present somewhere along the decent of a branchial tract (red arrows). They may begin along a mucosal surface and extend all the way to a cutaneous opening. The exact pathway varies depending on the cleft of origin. Contrast enhanced CT reveals a welldefined, unilocular, non-enhancing, water attenuating masses or tracts. Cysts are typically filled with mucoid material. . Branchial cleft cysts tend to be rounded and well defined whereas lymphangiomas are more infiltrative. Cysts can be distinguished from hemangiomas as the latter will show homogeneous rather than peripheral enhancement.
DDx: 2nd Branchial Cleft Cyst 1. 2. 3. 4. 5.
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Lymphangioma Dermoid Cysts Hemangiomas Paragangliomas Metastatic Adenopathy
DDx
Case 7a: 2nd Case of 2nd Branchial Cleft Cyst
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Case 7a: 2nd Case of 2nd Branchial Cleft Cyst
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Case 8: What is the most likely diagnosis?
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Tonsil Squamous Cell Carcinoma (SCCA)
Case 8: What is the most likely diagnosis?
Tonsillar SCCA are more strongly associated with human papillomavirus infection than are cancers of other regions of the neck. Presentation usually includes neck mass, enlarged tonsils, sore throat, ear pain, and bleeding from the mouth and is found 3-4 times more commonly in men. Tonsillar SCCA is also highly correlated with a history of alcohol abuse and smoking. SCCA of the oropharynx often has nodal spread with characteristic “watery” nodes (red arrow) that are often misdiagnosed as brachial cleft cysts. Most brachial cleft cyst present in the first decades of life where SCCA is more common after the 3 rd decade. One should exercise extreme caution in making the diagnosis of a branchial cleft cyst after the 3 rd decade, if there is a multilocular appearance, or nodular enhancement.
DDx: SCCA with Nodal Metastasis 1. 2. 3. 4.
Suppurative Adenopathy Benign Branchial Cleft Cyst Scrofula Diffuse Large B-Cell Lymphoma
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DDx
Case 9: What is the most likely diagnosis?
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2nd Branchial Cleft Cyst
Case 9: What is the most likely diagnosis?
This case demonstrates a cyst filled with material that is high in signal intensity on T1-weighted scans. This usually indicated a benign process, especially if it is homogeneous in signal intensity. The high T1 signal is due to T1 shortening of water by adjacent mucoproteinaceous material. The T2-weighted signal is usually low in these cases as well (red arrows). High T1-weighted signal intensity is unusual in tumors except for low grade papillary thyroid carcinoma that are mature enough to produce colloid. High T1 signal can also be seen in lymphangiomas that have chylous fat-containing secretions.
DDx: 2nd Branchial Cleft Cyst 1. Lymphangioma 2. Dermoid Cyst 3. Hemangioma 4. Hemorrhagic Neoplasm
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DDx
Thyroglossal Duct Cyst (TGDC)
Case 10: What is the most likely diagnosis?
Thyroglossal duct cysts are the most common congenital neck cyst. They are usually located near midline when above the hyoid bone and slightly off-midline when below the hyoid bone. A TGDC develop from persistence of an epithelial tract along the descent of the thyroid gland. This tract extends from the foramen cecum of the tongue to its final position in the anterior neck. The tract loops inferior and posterior to the hyoid bone. Normally this duct obliterates early in fetal life. TGDC usually present in the first two decade of life with intermittent midline or para-midline upper neck swelling. They are rarely so far lateral as to be confused with a branchial cleft cyst. TGDC usually present as a well-defined “cystic” mass with peripheral enhancement due to the epithelial lining (red arrows). When infected, there may be more ill-defined margins due to adjacent cellulitis. Sometimes islands of thyroid tissue may line the walls of the cyst. Presentation often includes dysphagia, dysphonia, draining sinus, fever, and an enlarging neck mass.
DDx: TGDC 1. Lymphatic Malformation 2. Dermoid Cyst 3. Ranula 4. Vallecular Cyst 5. Lymphadenopathy
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DDx
Thyroglossal Duct Cyst
Case 11: What is the most likely diagnosis?
Some TGDC will present as a cystic mass embedded within the tongue at the junction of the anterior 2/3 rds and posterior 1/3rd (red arrows). TGDC may occasionally be so large that they can cause respiratory distress. A suprahyoid location of TGDC is seen in about 20% of cases. Suprahyoid cysts are usually midline while infrahyoid cysts are slightly off midline.
DDx: TGDC 1. Ranula 2. Lymphatic Malformation 3. Dermoid-Epidermoid Cyst
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DDx
DDx: Ectopic Lingual Thyroid Gland 1. 2. 3. 4. 5.
Case 12: What is the most likely diagnosis?
SCCA of the Base of Tongue Lymphoma Lingual Hyperplasia Ectopic Thyroid Adenoma/Goiter/Hyperplasia/Thyroiditis/Carcinoma Metastasis
Ectopic Thyroid Gland (Lingual Thyroid Gland) Ectopic thyroid tissue is an uncommon entity, resulting from an aberrant migration of the gland. Thyroid ectopia can be found anywhere along the path of descent (thyroglossal duct tract) near the midline of the neck. An ectopic gland is 4x more likely in females. Lingual thyroid tissue appears on CT and MRI as a mass extending from the mucosal surface of the tongue base near the foramen cecum. The mass appears hyperdense on precontrast CT and demonstrates homogeneous enhancement (red arrow). Radionuclide imaging can confirm the presence of functioning ectopic thyroid tissue. An ectopic gland may be the only functioning thyroid tissue as in this case (blue arrows).
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DDx
Dermoid Cyst of the Floor of the Mouth
Case 13: What is the most likely diagnosis?
A dermoid cyst is a hamartomatous tumor of developmental origin. They may be intra- or extracranial. The periphery of the tumor is usually well-defined and is often covered by a thick, dermis-like cyst wall (blue arrow). The cyst is usually of fat density but may contain sebaceous glands and/or skin adnexa. MRI or CT is useful in diagnosing dermoid cysts by their characteristic fatty content or fat droplets. Fat globules are occasionally be seen in larger lesions on T1-weighted images as well-defined hyperintense rounded lesions (red arrow) that fatsuppress. The floor of the mouth is a common location for extracranial cysts.
DDx: Dermoid Cyst 1. 2. 3. 4. 5. 6.
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Epidermoid Cyst Lipoma Liposarcoma Sebaceous Cyst Pilomatrixoma Steatocystoma
DDx
Case 14: What is the most likely diagnosis?
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DDx: Simple Ranula
Case 14: What is the most likely diagnosis?
1. Dermoid Cyst 2. Epidermoid Cyst 3. Lymphangioma - Cystic Hygroma
Simple Ranula A simple ranula is a post-obstructive retention cyst of sublingual gland drainage that occurs as a result of trauma or inflammation leading to dilatation of the sublingual ducts (Rivini, Bartholin). Simple ranulas are located superior to the mylohyoid muscle and in the sublingual space (red arrows). Simple ranulas are usually true cysts with the lining formed by the sublingual gland capsule. Rarely the ducts can also rupture with spillage of mucin or fluid into the surrounding soft tissues. When the ranula is quite large it may extend posterior and inferior to the mylohyoid muscle and is termed a “plunging” ranula. Typical CT findings include smooth, well-delineated cystic lesions with a uniformly thin, non-enhancing wall. Ranulas have a high signal intensity on T2-weighted images but varies with protein content. Infected ranulas may have thickened enhancing walls and cannot be easily distinguished from an abscess.
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DDx
External Laryngocele
Case 15: What is the most likely diagnosis?
External laryngocele presents as a mass usually situated laterally between the superior border of the thyroid cartilage and the hyoid bone in the area of the thyrohyoid membrane. External laryngocele arise as a dilatation of the laryngeal ventricle and may contain either air (red arrows) or mucous. A internal laryngocele is located within the paraglottic space while an external laryngocele extends through the thyrohyoid membrane outside the larynx. They are probably caused by prolonged increased intralaryngeal pressure and a lack of normal thyroarytenoid muscle sphincteric action. This results in prolonged elevation of intralaryngeal pressure that is transmitted to the saccule of the ventricle, which may dilate into a laryngocele. When infected, they are termed a laryngopyocele
DDx: External Laryngocele 1. 2. 3. 4.
Laryngeal Neoplasm Submucosal Cysts Laryngopyocele Thyroplasty
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DDx
Case 16: What is the most likely diagnosis?
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Case 16: What is the most likely diagnosis?
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DDx: Zenker’s Diverticulum 1. 2. 3. 4.
Case 16: What is the most likely diagnosis?
Achalasia Neurenteric Duplication Cyst Killian-Jamison Diverticulum Esophageal Motility Disorder
Zenker’s Diverticulum Zenker’s Diverticulum is the most common form of esophageal diverticulum. Arising from increased pressure in the oropharynx during swallow against a closed esophageal sphincter. Intradiverticular filling defects usually represent food. These diverticulum usually present in people older than 50 and especially in the 7th and 8th decades of life. The optimal method of diagnosis is a barium swallow esophogram. Patients usually have a posterior midline pouch greater than 2 cm in diameter arising just above the cricopharyngeus muscle (red arrows). Patients often present with dysphagia, regurgitation of undigested food, aspiration, noisy deglutition, halitosis, and changes in their voice. The diverticulum is rarely palpable. A Killian-Jamieson diverticulum occurs just below the upper esophageal sphincter. These are seldom larger than 1.5 cm, are less frequent than Zenker's diverticulum, and are usually asymptomatic.
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DDx
Lymphatic Malformation Below Floor of Mouth
Case 17: What is the most likely diagnosis?
Lymphatic malformations (LM) are dilated collections of abnormal vascular channels and spaces that contain lymphatic fluid. They result from failure of normal embryogenesis of lymphatic vessels during fetal development. LM of the floor of the tongue and floor of the mouth can be associated with chronic airway problems, recurrent infection, and speech abnormalities. They are usually low in CT attenuation, poorly marginated ,and are typically multi-spatial (red arrows). They may also contain subacute blood products, which is easily seen as blood-fluid levels on CT or MR. Pure LM are non-enhancing, which differentiates them from venous malformations.
DDx: Lymphatic Malformation 1. 2. 3.
Ranula Lipoma Resolving Hematoma
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DDx
DDx: Cystic Hygroma 1. 2. 3. 4.
Case 18: What is the most likely diagnosis?
Teratoma Hemangioma Hemorrhagic Neoplasm Abscess
Macrocystic Cystic Hygroma (Lymphangioma) Cystic hygromas may be microcystic or macrocystic in nature. Macrocystic lymphangioma are defined as containing spaces that are < 2 cm in size (red arrows). In 80% of instances, cystic hygromas are located in the cervico-facial region. More than 60% are clearly visible at birth and up to 90% become overt before the age of two. CT and MR scans demonstrate multicompartmental, multicystic, homogeneous, non-invasive cystic appearing lesions. They are of low CT attenuation. Blood products or sedimentation levels are often seen within the lesion. (blue arrow}. Lymphangiomas are more common in patients with Turner syndrome, Trisomy 21, Noonan’s and Klinefelter’s syndromes.
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DDx
DDx: Cystic Hygroma
nd Case Case of Macrocystic Cystic Hygroma Teratoma 18a: 2
1. 2. 3. 4.
Hemangioma Hemorrhagic Neoplasm Abscess
Macrocystic Cystic Hygroma (Lymphangioma) Cystic hygromas may be microcystic or macrocystic in nature. Macrocystic lymphangioma are defined as containing spaces that are < 2 cm in size (red arrows). In 80% of instances, cystic hygromas are located in the cervico-facial region. More than 60% are clearly visible at birth and up to 90% become overt before the age of two. CT and MR scans demonstrate multicompartmental, multicystic, homogeneous, non-invasive cystic appearing lesions. They are of low CT attenuation. Blood products or sedimentation levels are often seen within the lesion. (blue arrow}. Lymphangiomas are more common in patients with Turner syndrome, Trisomy 21, Noonan’s and Klinefelter’s syndromes. .
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DDx
Case 19: What is the most likely diagnosis?
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Carotid Body Tumor
Case 19: What is the most likely diagnosis?
Carotid Body Tumors (CBT) arise from the nonchromaffin paraganglioma cells primarily located in the adventitial layer of blood vessels. Initially, CBT are asymptomatic and slow growing. These tumors tend to surround the external and internal carotid arteries without any significant compression. Patients often present with pain, hoarseness, dysphagia, Horner’s syndrome, tongue paresis and vertigo. Non-contrast T1-weighted MR images demonstrate a heterogeneous mass with isointense signal intensity that splays the carotid artery bifurcation vessels. There may be multiple serpentine areas of low signal intensity representing flow voids throughout the mass giving it a “salt-and-pepper appearance”. Arteriography or MRA usually shows the pathognomonic tumor blush between the internal and external carotid arteries (red arrows).
DDx: Carotid Body Tumor 1. 2. 3. 4.
Glomus Vagale Schwannoma Thyroid Ca with Nodal Mets Vascular Mets
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DDx
Case 20: What is the most likely diagnosis?
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Glomus Vagale
Case 20: What is the most likely diagnosis?
A glomus vagale is a tumor that arises from paraganglia in and around the vagus nerve. Glomus bodies are found within the vagus nerve and its ganglia. Most glomus vagale tumors manifest as a painless neck mass (red arrows) near the angle of the mandible. There may be lower cranial neuropathies; dysphagia, palatal weakness, and tongue hemiatrophy. Large tumors may contain necrotic, calcified, or hemorrhagic foci with varying degrees of heterogeneous enhancement. A characteristic salt-and-pepper appearance may be seen on T1- and T2-weighted images. These lesions demonstrate intense contrast enhancement. Glomus vagale tumors usually displace the internal carotid artery anteriorly and the internal jugular vein posteriorly.
DDx: Glomus Vagale 1. 2. 3. 4.
Glomus Jugulare Tumor Carotid Body Tumor Schwannoma Vascular Metastases
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DDx
DDx: Lymphatic Malformation
Case 21: What is the most likely diagnosis?
1. Hemangioma 2. Plexiform Neurofibroma 3. Myofascitis
Facial Lymphatic Malformation Lymphatic malformations (LM) are dilated collections of abnormal vascular channels and spaces that contain lymphatic fluid. They result from failure of normal embryogenesis of lymphatic vessels during fetal development. They are usually low in CT attenuation, poorly marginated ,and are typically multi-spatial (red arrows). They may also contain subacute blood products, which is easily seen as blood-fluid levels on CT or MR. Pure LM are non-enhancing, which differentiates them from venous malformations.
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DDx
Plexiform Neurofibroma Along Cranial Nerves 9-11
Case 22: What is the most likely diagnosis?
Plexiform neurofibromas are elongated, multi-nodular lesions involving multiple fascicles of a large nerve or multiple trunks of a nerve plexus. With few exceptions, plexiform neurofibromas are pathognomonic of NF1. The neurogenic origin of lesions can often be suspected by bony expansion of neural foramina (red arrows). Aggressive neoplasms of the neck can extend into the neural foramina but do not usually enlarge the foramina. Cranial nerves with a sensory components (V, IX, X) are involved more frequently than pure motor nerves (XI, XII). Large neurofibromas of major nerves and plexiform variants should be carefully screened for the presence of anaplastic features. CT or MRI usually shows a prominently enhancing mass that extends along the expected course of a cranial nerve.
DDx: Plexiform Neurofibroma 1. 2. 3. 4.
Multiple Hemangiomas Metastasis Venolymphatic Malformations Sarcoma
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DDx
Lipoma
Case 23: What is the most likely diagnosis?
Lipomas are the most common benign mesenchymal tumor, arising in any location where fat is normally present. They are present in approximately 1% of the general population but are most common in the fifth and sixth decades of life, Imaging is usually diagnostic with little in the differential. On CT scans, a lipoma is isodense with normal subcutaneous fat. Composed almost entirely of mature fat, lipomas appear as relatively well-circumscribed, homogeneous masses (red arrows) with a thin capsule. As compared to a liposarcoma, lipomas do not contain tissue of soft tissue attenuation and do no enhance with contrast. Treatment is usually unnecessary unless the tumor becomes painful , exhibits growth, or restricts movement.
DDx: Lipoma 1. Dermoid Cyst 2. Madelung Disease Case 1 3. HIV Lipodystrophy Syndrome 4. Liposarcoma
Case 2
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DDx
Peritonsillar Abscess and Suppurative Retropharyngeal Nodes
Case 24: What is the most likely diagnosis?
Peritonsillar tonsillar abscesses (PTA) are most common in the first 3 decades of life. Patients present with fever, toxicity, dysphagia, respiratory distress, drooling, and stridor. PTA (red arrows) occur between the tonsil and the capsule of the tonsil and often displace the tonsil anteromedially. Spread of infection to the draining retropharyngeal nodes may lead to development of a suppurative node (blue arrows) which represents an intranodal abscess. Rupture of this node will spill infection into the surrounding potential space leading to a retropharyngeal abscess (RPA). RPA is a potentially life threatening condition since there is little resistance to craniocaudal spread toward the mediastinum.
DDx: Peritonsillar Abscess and Suppurative Retropharyngeal Node 1. 2. 3. 4.
Retropharyngeal Cellulitis Prevertebral Abscess Retropharyngeal Hematoma Retropharyngeal Effusion secondary to Acute Calcific Prevertebral Tendinitis
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DDx
Case 25: What is the most likely diagnosis?
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Infantile Parotid Capillary Hemangioma
Case 25: What is the most likely diagnosis?
Hemangioma is characterized by a benign proliferation of vessels lined by endothelial cells. Hemangiomas account for approximately 0.4% of salivary gland tumors and occur almost exclusively in the parotid gland. They are most common in the first 6 years of life. The vast majority of these are of the “infantile” type meaning they have an initial proliferative phase and often involute by 6 years of age. Clinically, salivary hemangiomas present as asymptomatic swellings that may have a bluish hue to the overlying skin. MRI usually shows a slightly lobulated soft tissue mass with relatively homogeneous contrast enhancement. Intralesional flow-voids (red arrows) confirm the high vascularity of these lesion. Primary parotid malignancies and sarcomas tend to have a more heterogeneous appearance and variable contrast enhancement.
DDx: Parotid Hemangioma 1. Primary Parotid Malignancy 2. Rhabdomyosarcoma 3. Fibrosarcoma
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DDx
Internal Jugular Venous Thrombophlebitis - Deep Cervical Fasciitis
Case 26: What is the most likely diagnosis?
Thrombosis of the internal jugular vein may occur as a complication of head and neck infections, surgery, central venous access, and intravenous drug abuse. Central venous catheters now are the most common underlying cause. Potentially life threatening complications include cervical abscess, systemic sepsis and septic pulmonary embolism. The classic causes of thrombosis includes blood vessel trauma, stasis of blood flow, and a hypercoagulable state. CT findings include low-density intraluminal thrombus and a sharply defined enhancing vessel wall (due to contrast uptake by the vasa vasorum) (red arrows). Soft tissue edema and swelling around the IJ vein, adjacent musculature, and cervical fascia indicate deep cervical myofascitis.
DDx: Venous Thrombophlebitis - Cervical Fasciitis 1. Malignant Neoplasm with Extracapsular Nodal Spread 2. IJV Thrombosis and Perivascular Hematoma 3. Traumatic Vascular Thrombosis and Perivascular Hematoma
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DDx
DDx: Lymphangioma 1. 2. 3. 4.
Case 27: What is the most likely diagnosis?
Seroma Cervical Cellulitis Lipoma Liposarcoma
Lymphangioma of Lower Neck Lymphangioma is a benign hamartomatous malformation of lymphatic vessels; the majority occurring in the head and neck region. Thought to be a developmental malformation of vessels that have poor communication with the normal lymph system. Very large cystic spaces (red arrows) may be see in lesions proliferating in loose connective tissues and fascial spaces. Lymphangioma appears as multiple, intertwining lymph vessels in a loose fibrovascular stroma, sometimes with scattered aggregates of lymphoid tissue. There is no real encapsulation of the lesion, even when they appear well circumscribed clinically. These lesions can show intermittent enlargement with upper respiratory infections. They are of variable CT density, often approaching 0 Hounsfield units.
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DDx
Case 28: What is the most likely diagnosis?
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Periapical Abscess Subperiosteal Abscess Submandibular - Masticator Space Abscess
Case 28: What is the most likely diagnosis?
Periapical abscesses (purple arrows) of the 2nd or 3rd molar teeth may spread into the submandibular space because the long roots of these teeth are located inferior and posterior to the attachment of the mylohyoid muscle (red arrows) to the mandible. This subperiosteal abscess wraps around the inferior aspect of the mandible laterally into the region of the masseter muscle (blue arrows) (i.e. masticator space. Additionally, there is extension of infection along the submandibular duct into the submandibular gland.
DDx: Periapical Abscess Subperiosteal Abscess Submandibular - Masticator Space Abscess 1. Malignant Submandibular Gland Neoplasm 2. Floor of Mouth Squamous Cell Carcinoma
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DDx
DDx: Mandibular Osteomyelitis
Case 28a: Another Case; Diagnosis?
1. Osteosarcoma 2. Dental Granuloma 3. Radicular Cyst
Failed Dental Implant Mandibular Osteomyelitis Subperiosteal Abscess Mandibular Osteomyelitis (MO) is usually a consequence and extension of dental or periodontal infection. MO is rarely hematogenous or iatrogenic. In later stages it presents as pain and fever with swelling and redness of surrounding soft tissue. MO is often accompanied by acute suppurative inflammation with resorptive scalloping of margins of nonvital bone within large portions of the mandible. Upon radiologic examination, lesions appear as irregular, ill-defined, and predominantly radiolucent zones of bone destruction (red arrows). There may be accompanying subperiosteal abscess (blue arrows) or suppurative lymphadenopathy.
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DDx
Retropharyngeal Fluid-Edema (Likely Traumatic)
Case 29: What is the most likely diagnosis?
Edema fluid or lymph spilling into the retropharyngeal space is often secondary to venous or lymphatic obstruction or surrounding infection. Edema uniformly fills the retropharyngeal space from side to side. Secondly, edema has a smooth ovoid, rectangular, or “bow-tie” configuration on axial imaging and a diffuse craniocaudal distribution on sagittal images with tapered inferior and superior margins (red arrows). Edema will not cause wall thickening, nor will it enhance. Most cases resolve as cause of edema is treated. Ancillary findings include IJV thrombosis, adjacent neck infection, and, if secondary to acute calcific prevertebral tendinitis, there may be focal calcification anterior to C1-C2 in the longus colli tendons. The retropharyngeal space may extend into the mediastinum, often to the T4 level,
DDx: Retropharyngeal Fluid-Edema 1. 2. 3. 4.
Retropharyngeal Space Abscess Retropharyngeal Edema Other Etiology (IJV thrombosis, XRT, hypoproteinemia, anasarca, etc) Acute Calcific Prevertebral Tendinitis Infectious Spondylodiscitis
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DDx
Sjögren's Syndrome
Case 30: What is the most likely diagnosis?
Sjögren's Syndrome (SS) is one of the most prevalent autoimmune disorders. Nine out of 10 patients are women. The hallmark symptoms is dryness of the mouth and eyes (sicca symptoms).In addition, SS may cause skin, nose, and vaginal dryness, and may affect other organs of the body, including the kidneys, blood vessels, lungs, liver, pancreas, peripheral nervous system (distal axonal sensorimotor neuropathy) and brain. About half of the time SS occurs alone (Primary Sjögren’s) and the other half it occurs in the presence of another autoimmune connective tissue disease such as rheumatoid arthritis, lupus, or scleroderma (Secondary Sjögren’s). In the later stages of the disease multiple punctate calcifications (red arrows) may be seen in the parotid glands. Patients with SS have a higher rate of non-Hodgkin lymphoma compared to both patients with other autoimmune diseases and healthy people. About 5% of patients with Sjögren's syndrome will develop some form of lymphoid malignancy.
DDx: Sjögren's Syndrome 1. Parotid Sialolithiasis 2. Burnt-out Parotid Hemangioma 3. Prior Bilateral Parotitis
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DDx
Burnt-Out Masticator Space Infantile Hemangioma
Case 31: What is the most likely diagnosis?
The infantile type of capillary hemangioma are common lesion in the parotid space in the first 6 years of life but may also may involve the masticator space. They usually regress by age 6 and may only be recognizable by the presence of phleboliths (red arrows) within the nearly completely involuted lesion.
DDx: Burnt-Out Hemangioma 1. 2. 3. 4.
Metastasis With Dystrophic Calcification Old Masticator Space Abscess AVM Venolymphatic Malformation
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DDx
Case 32: What is the most likely diagnosis?
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Parotid Space Lymph-Hemangioma
Case 32: What is the most likely diagnosis?
Lymphangiomas are less common than hemangiomas in the parotid region. They are very subtle on CT scans because they are often isodense on both pre- and post-contrast studies, even though they are readily palpable. This is one of the reasons that MRI is the study of choice for evaluation of parotid masses. Lymphangiomas do not enhance with contrast since the sinusoidal spaces fill very slowly, if at all, following contrast administration. They are usually very hyperintense on T2-W MR and may have blood-fluid levels. Some lesions may have adjacent hemangiomatous or venolymphatic portions. This lesion has a tiny phlebolith (red arrow) that is in the hemangiomatous portion of the lesion.
DDx: Lymph-Hemangioma 1. Primary Parotid Malignancy 2. Parotid Abscess 3. 1st Branchial Cleft Cyst 4. Metastatic Adenopathy
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DDx
Case 33: What is the most likely diagnosis?
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Carotid Body Tumor
Case 33: What is the most likely diagnosis?
Carotid Body Tumors present as slow-growing, lateral cervical masses of the carotid bifurcation that are pulsatile. The majority of these lesions are painless, but may cause dysphagia, syncope with or without diaphoresis, nausea, trembling and blurred vision. The angiographic picture is characterized by spreading of the external and internal carotid arteries by the tumor (red arrows). It contains a vast net of tortuous, essentially regular vessels and large vascular lakes. The tumor vessels arise from the external carotid artery, which usually is displaced anteromedially or anterolaterally as the internal carotid is shifted laterally and backward.
DDx: Carotid Body Tumor 1. 2. 3. 4. 5.
Vascular Metastasis Glomus Vagale AVM Hemangioma Schwannoma
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DDx
Case 34: What is the most likely diagnosis?
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DDx: Retropharyngeal Abscess and Suppurative Adenopathy
Case 34: What is the most likely diagnosis?
1. Retropharyngeal Cellulitis 2. Retropharyngeal Hematoma 3. Prevertebral Abscess
4. Retropharyngeal Effusion secondary to Acute Calcific Prevertebral Tendinitis 5. Retropharyngeal Tumor
Retropharyngeal Abscess and Suppurative Adenopathy Suppurative adenopathy (SA) and retropharyngeal abscess (RA) are most common in pediatrics, patients. Patients often will present with fever, toxicity, dysphagia, respiratory distress, drooling, and stridor. SA usually results as a complication of pharyngeal infection when infected lymph drains into the retropharyngeal group of lymph nodes. SA represents the development of an abscess within the lymph node itself. Initially, the affected node will enlarge but maintains its normal oval shape since the capsule remains intact. With continued enlargement, however, the intranodal abscess will rupture (red arrow) and spread throughout the potential retropharyngeal space. A RA (blue arrow) is a potentially life threatening condition since the infection can spread unimpeded from the skull base to the upper mediastinum. RA often spread downward to the T4 level but if there is involvement of the adjacent “danger” space (black arrow) they may go as low as the diaphragm .
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DDx
Case 35: What is the most likely diagnosis?
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Case 35: What is the most likely diagnosis?
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2nd Branchial Cleft Cyst
Case 35: What is the most likely diagnosis?
Branchial cleft cysts are benign lesions that are thought to develop from failure of regression of embryologic precursor that form the gills in fish (branchia = gills {Greek}). Second branchial cleft cysts (SBCC) accounts for 95% of branchial anomalies. SBBC are usually located along the anteromedial border of the upper third of the sternocleidomastoid and just under the angle of the mandible. Branchial cleft cysts (red arrows) usually have high signal intensity on T1-W scans due to their high mucoid content. They are variable on T2-W images depending on the viscosity of the mucoproteinaceous fluid. Uninfected branchial cleft cysts do not significantly enhance on MRI. Branchial cleft cysts are more well-defined as compared to lymphangiomas.
DDx: 2nd Branchial Cleft Cyst 1. 2. 3. 4.
Lymphangioma Dermoid-Epidermoid Cysts Hemangiomas Paraganglioma
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DDx
Case 36: What is the most likely diagnosis?
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Necrotizing Fasciitis
Case 36: What is the most likely diagnosis?
Necrotizing fasciitis (NF) is a rare, but severe form of cellulitis usually caused by group A streptococci. There is a very high mortality rate with NF. It typically progresses quite rapidly leading to necrosis of skin, fascia, and underlying tissues. Asymmetrical facial edema, skin thickening, and presence of gas in the tissues (red arrows) is commonly found. The cellulitis tends to track along the myofascial planes of the neck. Involvement of surrounding muscle and vessels usually occurs a bit later. NF typically tracts into the carotid space since this space is surrounded by portions of all three layers of the deep cervical fascia, Carotid space involvement may, in turn, cause IJV thrombophlebitis and carotid occlusion. Once in the carotid sheath, NF can then spread along these vessels into the mediastinum. CT scanning is useful in identifying the extent of cellulitis, development of associated abscess, presence of air, and development of septic vascular thrombosis.
DDx: Necrotizing Fasciitis 1. 2. 3. 4.
Anasarca Superior Vena Cava Obstruction Toxic Shock Syndrome Anaphylactic Edema
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DDx
DDx: Periapical and Buccal Space Abscess
Case 37: What is the most likely diagnosis?
1. Buccal Space SCCA 2. Lymphoma 3. Minor Salivary Gland Neoplasm
Periapical Abscess of Tooth #5Subperiosteal Abscess Buccal Space Abscess Periapical abscess (PA) begin as an infection in the pulp chamber of a carious tooth. The infection spreads to the aperture of the tooth root where it gradually demineralizes and erodes the adjacent bone resulting in a localized abscess. The maxillary or mandibular teeth can be involved. Over time PA can break out through the inner or outer cortex of the maxilla or mandible extend into the surrounding subperiosteal space. Pus from these foci can track in various directions, including toward the buccal mucosa. CT will show a radiolucent area when an apical abscess has been preset for 2 or 3 weeks (red arrows). Caries may also be seen between two adjacent teeth, and the affected tooth may be impacted.
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DDx
DDx: Nodal Metastasis - SCCA 1. 2. 3. 4.
Case 38: What is the most likely diagnosis?
Branchial Cleft Cyst Papillary Thyroid CA Tuberculous Lymphadenitis Suppurative Lymphadenitis
DDx: Nodal Metastasis - SCCA Nodal metastasis from SCCA of the head and neck may occasionally present with “watery-appearing” neck nodes (red arrows) that must be distinguished from branchial cleft cysts. Often the primary tumor may not be readily apparent. The differential diagnosis of low attenuation “nodes” must include non-neoplastic (suppurative node, TB lymphadenitis, branchial cleft cyst) as well as neoplastic (H&N SCCA, papillary thyroid CA) causes. Watery-appearing nodes are especially common with oropharyngeal H&N SCCA. Great care should be made in diagnosing branchial cleft cysts in adult patients; especially if there are septations, mural nodules, or non-uniformity of the cyst wall.
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DDx
Case 39: What is the most likely diagnosis?
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Spontaneous Retropharyngeal Hematoma
Case 39: What is the most likely diagnosis?
Spontaneous retropharyngeal hematoma (RH) is a rare cause of acute noninflammatory neck swelling that may rapidly evolve to cause upper airway obstruction. Most documented causes have been: coagulopathic states, trauma, carotid artery rupture, metastasis, angiographic procedures, and foreign body ingestion. Classical presentation is “Capp’s triad” of tracheal/esophageal compression, anterior displacement of trachea, and subcutaneous bruising over neck and anterior chest. Precontrast T1-MRI shows a peripherally hyperintense mass (red arrows) that extends from the upper nasopharynx into the hypopharyngeal region displacing the trachea, larynx, and esophagus anteriorly . T2-weighted gradient-echo images show the mass to be hypointense due to deoxyhemoglobin (blue arrows). Postcontrast T1-W image shows minimal peripheral enhancement (green arrow).
DDx: Retropharyngeal Hematoma 1. 2. 3. 4.
Retropharyngeal Abscess Pharyngeal Neoplasm With Retrovertebral Spread Prevertebral Extension of Vertebral Neoplasm Liposarcoma
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Carotid Body Tumor
Case 40: What is the most likely diagnosis?
Carotid Body Tumors (CBT) arise from the nonchromaffin paraganglion cells primarily located in the adventitial layer of blood vessels at the carotid bifurcation. There is a higher incidence of CBTs in individuals living at high altitudes. Initially, CBTs are asymptomatic and slow growing. These tumors tend to splay the external and internal carotid arteries without any significant compression. Patients often present with pain, hoarseness, dysphagia, Horner’s syndrome, tongue paresis and vertigo. Contrast-enhanced CT images demonstrate a markedly enhancing soft-tissue mass (red arrows) centered at the carotid bifurcation with splaying of the internal and external carotid arteries.
DDx: Carotid Body Tumor 1. 2. 3. 4. 5.
Schwannoma Vascular Metastasis Aneurysm Hemangioma Venolymphatic Malformation
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DDx
Periapical Abscess Subperiosteal Abscess Masticator Space Abscess
Case 41: What is the most likely diagnosis?
This patient had a large dental cavity (blue arrow) and periapical abscess of tooth # 1. A periapical abscess that originates in molar teeth can result in subperiosteal abscess that can involve several spaces of the head and neck including the masticator space (MS) (red arrows). These abscesses can easily extend into the MS because the medial pterygoid and masseter muscles attach to the angle of the mandible in close proximity to the roots of the 3rd mandibular molar teeth. A periapical abscess in the mandible can perforate the bone at the least resistant and weakest portion, which is the lingual side of the molar region.
DDx: Masticator Space Abscess 1. 2. 3. 4.
Masticator Metastasis From H&N SCCA Masticator Space Hemangioma Subacute Denervation Atrophy Pterygoid Muscle Submandibular Sialoadenitis
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DDx
Ludwig’s Angina
Case 42: What is the most likely diagnosis?
Ludwig’s angina is a dramatic, life-threatening, soft-tissue infection of the floor of the mouth and neck. Airway control is of paramount importance combined with immediate antibiotic therapy, and surgical drainage to decrease mortality. Etiology is usually from an odontogenic infection. Ludwig’s angina is a rapidly progressing polymicrobial cellulitis and myofascitis that spreads via connective tissue to the anterior neck and inferiorly to the mediastinum. CT can confirm the presence of gas in the soft tissues and extensive edema of the floor of the mouth and anterior neck (red arrows). CT will also reveal the extent of soft-tissue swelling as well as severity of airway compromise (blue arrows).
DDx: Ludwig’s Angina 1. Sublingual Sialadenitis 2. Lymphangioma 3. Oral Tongue Carcinoma 4. Sublingual Hematoma 5. Angioneurotic Edema
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DDx
Intratonsillar Abscess
Case 43: What is the most likely diagnosis?
CT shows enlargement and low attenuation (red arrows) within the left palatine tonsil with faint rim enhancement. The tonsil is not displaced anteromedially as would be the case with peritonsillar abscesses. Intratonsillar abscesses are caused by obstruction of a tonsillar crypt leading to post-obstructive abscess formation. A true peritonsillar abscess may develop if the intratonsillar abscess does not spontaneously rupture and evacuate. Intratonsillar abscesses, in most cases, may be successfully treated with antibiotics while peritonsillar abscesses usually require surgical drainage.
DDx: Intratonsillar Abscess 1. 2. 3. 4.
Tonsillitis Peritonsillar Abscess Tonsillar Neoplasm Mononucleosis
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Peritonsillar Abscess
Case 44: What is the most likely diagnosis?
Peritonsillar abscess is the most common deep infection of the head and neck in children and young adults, often progressing from pharyngitis or tonsillitis. Peritonsillar abscesses form in the potential space between the palatine tonsil and its capsule, posterolaterally. A distinguishing clinical feature is inferior and anteromedial displacement of the infected tonsil (blue arrows) with contralateral deviation of the uvula. Many patients will have a thickened, muffled voice often described as having a “hot potato” quality. Contrast-enhanced CT in these 2 patients show areas of low attenuation surrounded by peripheral enhancement (red arrows) suggestive of abscess formation. Diffuse soft tissue edema with loss of the fat planes, retropharyngeal adenopathy, retropharyngeal abscess, and carotid sheath abscess, airway compromise may also be seen on CT.
DDx: Peritonsillar Abscess 1. 2. 3. 4.
Tonsillitis Intratonsillar Abscess Tonsillar Neoplasm Mononucleosis
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DDx
Case 45: What is the most likely diagnosis?
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Acute Calcific Prevertebral Tendonitis
Case 45: What is the most likely diagnosis?
Acute calcific prevertebral tendonitis often presents in patients with pain and stiffness in the neck associated with odynophagia and retropharyngeal soft-tissue swelling. Deposition of calcium hydroxyapatite in the oblique tendon and fibers of the longus colli and capitus muscles is seen (red arrows). Calcific crystals are presumed to be deposited from secondary inflammatory tendonitis. These calcific densities are best seen on 2D sagittal reformatted images and are often accompanied by fluid collection extending into the retropharyngeal space. The retropharyngeal fluid collection extends in all directions and shows no enhancing wall versus abscess.
DDx: Acute Calcific Prevertebral Tendonitis 1. Retropharyngeal Abscess 2. Infectious Spondylitis 3. Traumatic Effusion
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Case 45a: A 2nd Case of Acute Calcific Prevertebral Tendonitis
Courtesy of Pat Hudgins
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Case 45b: A 3rd Case of Acute Calcific Prevertebral Tendonitis
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Courtesy of Doug Phillips
Periapical Abscess Subperiosteal Abscess Sublingual Space Abscess
Case 46: What is the most likely diagnosis?
A periapical abscess that originates from the 1 st or 2nd molar teeth as well as from the premolar, canine, and incisor teeth can result in a sublingual space abscess if they erode into through the lingual cortex of the mandible (red arrows). A periapical abscess usually perforates the mandibular cortex where there is less resistant which is on the lingual side in the molar region. Sublingual space abscesses may then lead to the development of Ludwig’s angina.
DDx: Sublingual Space Abscess 1. 2. 3. 4. 5.
Ludwig’s Angina Sublingual Space Neoplasm Sublingual Gland Sialoadenitis Lymphangioma Ranula
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DDx
DDx: Multinodular Goiter
Case 47: What is the 1. Lymphoma most likely diagnosis? 2. Hashimoto’s Thyroiditis 3. Graves Disease
Multinodular Goiter The incidence of goiter, diffuse and nodular, is very much dependent on the status of iodine intake of the population. In areas of iodine deficiency, goiter prevalence may be very high. Especially in goiters of longstanding duration multinodularity frequently develops. The incidence of multinodular goiter in areas with sufficient iodine intake has been found to be around 6% with a female/male ratio of 13:1. There is an increased frequency over 45 years of age. Nodular goiter may be the result of any chronic low-grade, intermittent stimulus leading to thyroid hyperplasia. In response to iodide deficiency, the thyroid first goes through a period of hyperplasia as a consequence of the resulting TSH stimulation, but eventually, possibly because of iodide repletion or a decreased requirement for thyroid hormone, enters a resting phase characterized by colloid storage and the histologic picture of a colloid goiter. Repetition of these two phases of the cycle would eventually result in the formation of nontoxic multinodular goiter . By the time the goiter is well developed, serum TSH levels and TSH production rates are usually normal. (red arrows).
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DDx
DDx: Hodgkin’s Lymphoma
Case 48: What is the most likely diagnosis?
1. Reactive Adenopathy
2. Non-Hodgkin’s Lymphoma 3. SCCA Adenopathy 4. Malignant Melanoma 5. Cat-Scratch Fever 6. Rosai-Dorfman Disease
Hodgkin’s Lymphoma Hodgkin's lymphoma, a neoplasm originating from lymphocytes, was named after Thomas Hodgkin, who first described abnormalities in the lymph system in 1832. Hodgkin lymphoma begins when a lymphocyte (usually a B cell) becomes abnormal and forms the multinucleated Reed-Sternberg cell. Hodgkin's lymphoma is usually characterized by the orderly spread of neoplasm from one lymph node group to another (red arrows). The spleen and liver may be involved. Waldeyer’s ring is not as frequently involved with Hodgkin’s lymphoma as compared to non-Hodgkin’s lymphoma. The disease occurrence shows two peaks: the first in young adulthood (age 15–35) and the second in those over 55 years old. There is an estimated 9,000 new cases in the United States with 1,300 annual deaths. Past infection with the Epstein-Barr virus (EBV) is thought to contribute to some cases. Patients with HIV infection are more at risk than the general population. The 10-year overall survival rate is more than 90% for all stages.
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DDx
DDx: Retropharyngeal and Carotid Space Abscesses
Case 49: What is the most likely diagnosis?
1. Retropharyngeal and Carotid Space Hematoma 2. Retropharyngeal Effusion
3. Acute Calcific Prevertebral Tendinitis 4. Retropharyngeal Sarcoma
Retropharyngeal and Carotid Space Abscesses Retropharyngeal space abscesses (red arrows) can easily spread to the carotid spaces (blue arrows) since the two spaces share part of the same fascia (deep cervical fascia). The infection within the carotid space can also result in severe spasm of the internal carotid arteries, venous thrombophlebitis, occlusion of the internal jugular veins, and spread downward into the mediastinum.
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DDx
DDx: Osteochondroma of Zygomatic Arch
Case 50: What is the most likely diagnosis?
1. Osteosarcoma
2. Chondrosarcoma
3. Fibrous Dysplasia 4. Post-traumatic Myositis Ossificans
Osteochondroma of Zygomatic Arch Osteochondromas of the facial bones are quite uncommon. This lesion seen to arise from the inferior aspect of the zygomatic arch (red arrows) and is partially embedded within the masseter and temporalis muscles (blue arrows). No periosteal bone formation or true bony matrix is seen to suggest an aggressive bone neoplasm. The sharp outer cortex, presence of normal appearing internal bony septa, and normal cancellous bone would be atypical for fibrous dysplasia.
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DDx